The present invention relates generally to electronic circuits. More particularly, embodiments of the present invention relate to circuits and systems for an electrically resettable fuse device for integrated circuit applications.
In electronics, a fuse is a low resistance resistor that acts to provide overcurrent protection. Short circuit, overloading, mismatched loads or device failure are possible reasons for excessive current. A conventional fuse is usually a metal wire that melts when too much current flows, which interrupts the circuit in which it is connected, so that further damage by overheating or fire is prevented. Overcurrent protection devices are essential in electrical systems to limit threats to human life and property damage.
In integrated circuit (IC) applications, a fuse or anti-fuse device can be used to implement circuit design options. For example, a metal fuse can be cut open with a laser. In other cases, a high voltage can be used to breakdown a metal-insulator-metal structure to establish a conductive path.
Most conventional fuses for overcurrent protection are a ‘one shot’, non-resettable device which must be replaced once they have been activated or blown. On the other hand, conventional self-resetting fuses use a thermoplastic conductive element thermistor that impedes the circuit during an overcurrent condition by increasing device resistance. The thermistor is self-resetting in that when current is removed, the device will cool and revert to low resistance. These devices are often used in aerospace/nuclear applications where replacement is difficult, or on a computer motherboard so that a shorted mouse or keyboard does not cause motherboard damage.